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5G

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5G
5th generation mobile network (5G) logo.jpg
3GPP's 5G logo
International standardBCI-2017
Developed byBCI[disambiguation needed]

5G is the latest generation of cellular mobile communications. It succeeds the 4G (LTE/WiMax), 3G (UMTS) and 2G (GSM) systems. 5G performance targets high data rate, reduced latency, energy saving, cost reduction, higher system capacity, and massive device connectivity. The first phase of 5G specifications in Release-15 will be completed by April 2019 to accommodate the early commercial deployment. The second phase in Release-16 is due to be completed by April 2020 for submission to the International Telecommunication Union (ITU) as a candidate of IMT-2020 technology.[1]

The ITU IMT-2020 specification demands speeds up to 20 Gbps, achievable with wide channel bandwidths and massive MIMO.[2] 3rd Generation Partnership Project (3GPP) is going to submit 5G NR (New Radio) as its 5G communication standard proposal. 5G NR can include lower frequencies, below 6 GHz, and mmWave, above 15 GHz. However, the speeds in early deployments, using 5G NR software on 4G hardware (non-standalone), are only slightly higher than new 4G systems, estimated at 15% to 50% faster.[3][4] Simulation of standalone eMBB deployments showed improved throughput by 2.5× below 6 GHz and by nearly 20× at millimeter waves.[5]

Performance targets

5G systems in line with IMT-2020 specifications[6] are expected to provide enhanced device and network-level capabilities, tightly coupled with intended applications. The following eight parameters are key capabilities for IMT-2020 5G:

Capability Description 5G target Usage scenario
Peak data rate Maximum achievable data rate 20 Gbit/s eMBB
User experienced data rate Achievable data rate across the coverage area 1 Gbit/s eMBB
Latency Radio network contribution to packet travel time 1 ms URLLC
Mobility Maximum speed for handoff and QoS requirements 500 km/h eMBB/URLLC
Connection density Total number of devices per unit area 106/km2 MMTC
Energy efficiency Data sent/received per unit energy consumption (by device or network) Equal to 4G eMBB
Spectrum efficiency Throughput per unit wireless bandwidth and per network cell 3–4x 4G eMBB
Area traffic capacity Total traffic across coverage area 1000 (Mbit/s)/m2 eMBB

Note that, for 5G NR, according to 3GPP specification when using spectrum below 6 GHz, the performance would be closer to 4G.

Usage scenario

ITU-R have defined three main types of usage scenario that the capability of 5G NR is expected to enable. They are Enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communications (URLLC), and Massive Machine Type Communications (mMTC).[7]

Enhanced Mobile Broadband (eMBB)

Enhanced Mobile Broadband (eMBB) refers to the use case of using 5G as an evolution to 4G LTE mobile broadband services with faster connection with higher throughput and more capacity. 5G would need to deliver higher capacity, enhance connectivity, and higher user mobility to match these demands, which would require capabilities in the above table with eMBB mark to deliver.[8]

Ultra Reliable Low Latency Communications (URLLC)

Massive Machine Type Communications (mMTC)

Advantages

Speed

5G promises superior speeds in most conditions to the 4G network. Qualcomm presented a simulation at Mobile World Congress[9][10][11] that predicts 490 Mbit/s median speeds for 3.5 GHz 5G Massive MIMO and 1.4 Gbit/s median speed for 28 GHz mmWave.[12] 5G NR speed in sub-6 GHz bands can be slightly higher than the 4G with a similar amount of spectrum and antennas,[13][14] though some 3GPP 5G networks will be slower than some advanced 4G networks, such as T-Mobile's LTE/LAA network, which achieves 500+ Mbit/s in Manhattan.[15]

The 5G specification allows LAA (License Assisted Access) as well but it has not yet been demonstrated. Adding LAA to an existing 4G configuration can add hundreds of megabits per second to the speed, but this is an extension of 4G, not a new part of the 5G standard.[15]

Low communication latency

Latency is the time it takes to pass a message from sender to receiver.[16] Low communication latency is one improvement in 5G. Lower latency could help 5G mobile networks enable things such as multiplayer mobile gaming, factory robots, self-driving cars and other tasks demanding quick response.

New use cases

Features of 5G network, including extreme high bandwidth, ultra low latency, and high density connections, are expected to enable many new use cases that are impossible to be done via older network standards.[17]

Standards

Initially, the term was defined by the International Telecommunication Union's IMT-2020 standard, which required a theoretical peak download capacity of 20 gigabits, along with other requirements for 5G networks.[18] Then, the industry standards group 3GPP have prepared the 5G NR (New Radio) standard together with LTE as their proposal for submission to the IMT-2020 standard.[19][20]

ITU has divided 5G network services into three categories: enhanced Mobile Broadband (eMBB) or handsets; Ultra-Reliable Low-Latency Communications (URLLC), which includes industrial applications and autonomous vehicles; and Massive Machine Type Communications (MMTC) or sensors.[21] Initial 5G deployments will focus on eMBB[22] and fixed wireless,[23] which makes use of many of the same capabilities as eMBB. 5G will use spectrum in the existing LTE frequency range (600 MHz to 6 GHz) and also in millimeter wave(mmWave) bands (24–86 GHz). 5G technologies have to satisfy ITU IMT-2020 requirements and/or 3GPP Release 15;[citation needed] while IMT-2020 specifies data rates of 20 Gbit/s, 5G speed in sub-6 GHz bands is similar to 4G.[13][14]

IEEE covers several areas of 5G with a core focus in wireline sections between the Remote Radio Head (RRH) and Base Band Unit (BBU). The 1914.1 standards focus on network architecture and dividing the connection between the RRU and BBU into two key sections. Radio Unit (RU) to the Distributor Unit (DU) being the NGFI-I (Next Generation Fronthaul Interface) and the DU to the Central Unit (CU) being the NGFI-II interface allowing a more diverse and cost-effective network. NGFI-I and NGFI-II have defined performance values which should be compiled to ensure different traffic types defined by the ITU are capable of being carried. 1914.3 standard is creating a new Ethernet frame format capable of carrying IQ data in a much more efficient way depending on the functional split utilized. This is based on the 3GPP definition of functional splits. Multiple network synchronization standards within the IEEE groups are being updated to ensure network timing accuracy at the RU is maintained to a level required for the traffic carried over it.

Air interface

5G NR

5G NR (New Radio) is a new air interface developed for the 5G network.[24] It is supposed to be the global standard for the air interface of 5G networks.[25]

Pre-standard implementations

  • 5GTF: The 5G network implemented by American carrier Verizon for Fixed Wireless Access in late 2010s uses an pre-standard specification known as 5GTF (Verizon 5G Technical Forum). The 5G service provided to customers in this standard is incompatible with 5G NR. There are plans to upgrade 5GTF to 5G NR "Once [it] meets our strict specifications for our customers," according to Verizon.[26]
  • 5G-SIG is another pre-standard specification of 5G developed by KT Corporation. It is the version of implementation deployed at Pyeongchang 2018 Winter Olympics.[27]

NB-IoT/eMTC

3GPP is going to submit evolution of NB-IoT and eMTC(LTE-M) as the 5G technology for the LPWA (Low Power Wide Area) use case.[28]

3GPP 5G phases

Phases 3GPP releases
Phase 1 Release 15
Phase 2 Release 16

Deployment

Development of 5G is being led by companies such as Qualcomm,[29] Huawei,[30] and Intel[citation needed] for modem technology and Nokia,[citation needed] Ericsson,[citation needed] ZTE,[citation needed] Cisco,[citation needed] and Samsung[citation needed] for infrastructure.

Worldwide commercial launch is expected in 2020. Numerous operators have demonstrated 5G as well, including Korea Telecom for the 2018 Winter Olympics[31][32] and Telstra at the 2018 Commonwealth Games.[33] In the United States, the four major carriers have all announced deployments: AT&T's[34] millimeter wave commercial deployments in 2018, Verizon's 5G fixed wireless launches in four U.S. cities and millimeter-wave deployments,[35] Sprint's launch in the 2.5 GHz band, and T-Mobile's 600 MHz 5G launch in 30 cities.[36] Vodafone performed the first UK trials in April 2018 using mid-band spectrum,[37] and China Telecom's initial 5G buildout in 2018 will use mid-band spectrum as well.[38] The world first service of 5G was in South Korea, as the South Korean telecoms deployed it all at once on 1 December 2018.[39]

Beyond mobile operator networks, 5G is also expected to be widely utilized for private networks with applications in industrial IoT, enterprise networking, and critical communications.

In December 2018, Nokia and Telefónica Deutschland start testing 5G in Berlin, with five sites.[40]

Spectrum

In order to support increased throughput requirements of 5G, large quantities of new spectrum (5G NR frequency bands) have been allocated to 5G, particularly in millimeter wave bands.[41] For example, in July 2016, the Federal Communications Commission (FCC) of the United States freed up vast amounts of bandwidth in underutilised high-band spectrum for 5G. The Spectrum Frontiers Proposal (SFP) doubled the amount of millimeter-wave (mmWave) unlicensed spectrum to 14 GHz and created four times the amount of flexible, mobile-use spectrum the FCC had licensed to date.[42] In March 2018, European Union lawmakers agreed to open up the 3.6 and 26 GHz bands by 2020.[43]

5G modems

Traditional cellular modem suppliers have significant investment in the 5G modem market. Qualcomm announced its X50 5G Modem in October 2016,[44] and in November 2017, Intel announced its XMM8000 series of 5G modems, including the XMM8060 modem, both of which have expected productization dates in 2019.[45][46] In February 2018, Huawei announced the Balong 5G01 terminal device[47] with an expected launch date for 5G-enabled mobile phones of 2018[48] and Mediatek announced its own 5G solutions targeted at 2020 production.[49] Samsung is also working on the Exynos 5G modem, but has not announced a production date.[50]

Modes of deployment

Initial 5G NR launches will depend on existing LTE 4G infrastructure in non-standalone (NSA) mode, before maturation of the standalone (SA) mode with the 5G core network.

Non-Standalone mode

Non-Standalone (NSA) mode of 5G NR refers to an option of 5G NR deployment that dependent on the control plane of existing LTE network for control functions, while 5G NR exclusively focused on user plane.[51][52] The advantage of doing so is reported to speed up 5G adoption, however some operators and vendors have criticized prioritizing the introduction of 5G NR NSA on the grounds that it could hinder the implementation of the standalone mode of the network.[53]

Standalone mode

Standalone (SA) mode of 5G NR refers to using 5G cells for both signalling and information transfer.[51] It includes the new 5G Packet Core architecture instead of relying on the 4G Evolved Package Core.[54][55] It mean it would allow the deployment of 5G without LTE network.[56] It is expected to have lower cost, better efficiency, and assist development of new use cases.[57]

Technology

New radio frequencies

The air interface defined by 3GPP for 5G is known as New Radio (NR), and the specification is subdivided into two frequency bands, FR1 (below 6 GHz) and FR2 (mmWave),[58] each with different capabilities.

Frequency range 1 (< 6 GHz)

The maximum channel bandwidth defined for FR1 is 100 MHz. Note that beginning with Release 10, LTE supports 100 MHz carrier aggregation (five × 20 MHz channels.) FR1 supports a maximum modulation format of 256-QAM while LTE has a maximum of 64-QAM, meaning 5G achieves significant throughput improvements relative to LTE in the sub-6 GHz bands. However LTE-Advanced already uses 256-QAM, eliminating the advantage of 5G in FR1.

Frequency range 2 (24–86 GHz)

The maximum channel bandwidth defined for FR2 is 400 MHz, with two-channel aggregation supported in 3GPP Release 15. The maximum Physical layer (phy) rate potentially supported by this configuration is approximately 40 Gbit/s. In Europe, 24.25–27.5 GHz is the proposed frequencies range.[59]

Massive MIMO

Massive MIMO (multiple input and multiple output) antennas increases sector throughput and capacity density using large numbers of antennae and Multi-user MIMO (MU-MIMO). Each antenna is individually-controlled and may embed radio transceiver components. Nokia claimed a five-fold increase in the capacity increase for a 64-Tx/64-Rx antenna system. The term "massive MIMO" was coined by Nokia Bell Labs researcher Dr. Thomas L. Marzetta in 2010, and has been launched in 4G networks, such as Softbank in Japan.[citation needed]

Edge computing

Edge computing is a method of optimizing cloud computing systems by taking the control of computing applications, data, and services away from some central nodes (the "core area"). In a 5G network, it would promote faster speeds and low-latency data transfer on edge devices.[60]

Small cell

Beamforming

Radio convergence

One expected benefit of the transition to 5G is the convergence of multiple networking functions to achieve cost, power and complexity reductions. LTE has targeted convergence with Wi-Fi via various efforts, such as License Assisted Access (LAA) and LTE-WLAN Aggregation (LWA), but the differing capabilities of cellular and Wi-Fi have limited the scope of convergence. However, significant improvement in cellular performance specifications in 5G, combined with migration from Distributed Radio Access Network (D-RAN) to Cloud- or Centralized-RAN (C-RAN) and rollout of cellular small cells can potentially narrow the gap between Wi-Fi and cellular networks in dense and indoor deployments. Radio convergence could result in sharing ranging from the aggregation of cellular and Wi-Fi channels to the use of a single silicon device for multiple radio access technologies.

NOMA (non-orthogonal multiple access)

NOMA (non-orthogonal multiple access) is a proposed multiple-access technique for future cellular systems. In this, same time, frequency, and spreading-code resources are shared by the multiple users via allocation of power. The entire bandwidth can be exploited by each user in NOMA for entire communication time due to which latency has been reduced and users' data rates can be increased. For multiple access, the power domain has been used by NOMA in which different power levels are used to serve different users. 3GPP also included NOMA in LTE-A due to its spectral efficiency and is known as multiuser superposition transmission (MUST) which is two user special case of NOMA.[61]

SDN/NFV

Channel coding

The channel coding techniques for 5G NR have changed from turbo in 4G to polar for the control channel and LDPC for the data channel.[62][63]

Operation in unlicensed spectrum

Like LTE in unlicensed spectrum, 5G NR will also support operation in unlicensed spectrum (NR-U).[64] In addition to License Assisted Access (LAA) from LTE that enable carriers to use those unlicensed spectrum to boost their operational performance for users, in 5G NR it will support standalone NR-U unlicensed operation which will allow new 5G NR networks to be established in different environments without acquiring operational license in licensed spectrum, for instance for localized private network or lower the entry barrier for providing 5G internet services to the public.[64]

Confusion

In various part of the world, carriers have launched numerous differently branded technologies like "5G Project" or "5G Evolution" which advertise improving existing networks with the use of "5G technology".[65][66] However, these pre-5G networks are actually existing improvement on specification of LTE networks that are not exclusive to 5G.[67][68]

Health and safety

The World Health Organization states that "A large number of studies have been performed over the last two decades to assess whether mobile phones pose a potential health risk. To date, no adverse health effects have been established as being caused by mobile phone use."[69] In a 2018 statement, the FDA said that "the current safety limits are set to include a 50-fold safety margin from observed effects of radiofrequency energy exposure".[70]

Regional progress

On 15 May 2018, Qatari telecommunications company Ooredoo launched the world's first commercial 5G network in several areas of the capital, Doha.[71]

Other applications

Digital television

3GPP have been studying mixed mode multicast and terrestrial broadcast based on equivalent of MBMS for 5G NR and a further development based on LTE's EnTV.[72]

Automobiles

5G Automotive Association have been promoting the C-V2X communication technology that is based on 5G NR for communication between vehicles and communication between vehicles and infrastructures.[73]

Automation (factory and process)

5G Alliance for Connected Industries and Automation - 5G-ACIA promotes 5G for factory automation and process industry.[74]

Public safety

Mission-critical push-to-talk (MCPTT) and mission-critical video and data are expected to be furthered in 5G.[75]

See also

References

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External links

Preceded by
4th Generation (4G)
Mobile telephony generations Succeeded by